hrm - that is interesting, i was under the impression that from 12mm upwards the lens functions fine, and lower than that it just has a circular image like a fisheye.  There is no problem with the mount - the sigma lens canon mounts are all (as far as i know) EF and not EF-S.

"In every colour, there's the light.
In every stone sleeps a crystal.
Remember the Shaman, when he used to say:
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